Tool replacing device

Abstract

A tool replacing device including a case member is disclosed. In the case member, engaging balls supported between a holding member and a movable member is projected into the holding member by an extruding surface of the movable member, resiliently urged by a second spring, thereby allowing a tool to be engaged. By pressing the movable member against a resilient urging force of the second spring, the engaging balls can be moved in the movable member. Also, since there are provided shock sensors for detecting a moving distance of the holding member holding the tool, collision or the like of the tool can be detected. Even if power supply is stopped, the present tool replacing device can hold the tool.

1. A tool replacing device wherein a mounting hole for a tool is provided on its distal end side from which the tool is inserted, and wherein its proximal end side is mounted to a tip portion of a robot arm, the tool replacing device comprising:
 a substantially cylindrical case member having a first extension portion, a second extension portion, and a third extension portion that extend toward an inner diameter side of the tool replacing device, and that are located on the distal end side, the proximal end side, and between the distal end side and the proximal end side, respectively; 
 a substantially cylindrical holding member located inside the case member, and having a fourth extension portion that extends toward an inner peripheral surface of the case member between the second extension portion and the third extension portion; and 
 a substantially cylindrical movable member located on the distal side of the holding member, and supported between the holding member and the case member, the movable member having a fifth extension portion extending toward the inner peripheral surface of the case member between the first extension portion and the third extension portion, 
 wherein the case member supports the holding member between the second extension portion and the fourth extension portion via a first elastic member so as to be movable in a cylindrical axis direction of the case member, and supports the movable member so as to be movable in the cylindrical axis direction of the case member, between the third extension portion and the fifth extension portion via a second elastic member, the case member including:
 a shock sensor that is located at an end face on the proximal end side of the third extension portion, and that detects a movement of the holding member by abutting against the fourth extension portion; and 
 a fluid supply hole for supplying a fluid to an end face on the distal end side of the fifth extension portion, and moving the movable member toward a direction opposite to a direction of a resilient urging force of the second elastic member, the fluid supply hole being located at an end face on the proximal end side of the first extension portion; 
 
 wherein the holding member includes a projection hole formed so that an engaging ball held between the movable member and the holding member is projectable toward an inner peripheral surface side of the holding member; and 
 wherein the movable member includes:
 an extruding surface that projects the engaging ball from the projection hole toward the inner peripheral surface side of the holding member by the end face on the distal end side of the fifth extension portion resiliently urged by the second elastic member abutting against an inner peripheral surface of the movable member, opposite to the engaging ball when the end face on the distal end side of the fifth extension portion abuts against the end face on the proximal end side of the first extension portion; and 
 a groove portion for accommodating the engaging ball that has moved from the projection hole to the inner peripheral side of the movable member when the fifth extension portion has been pressed against the resilient urging force of the second elastic member by the fluid supplied through the fluid supply hole and the movable member has moved to the proximal end side, the groove portion being located in the inner peripheral surface of the movable member, opposite to the engaging ball. 
 
 
     
     
       2. A tool replacing device wherein a mounting hole for a tool is provided on its distal end side from which the tool is inserted, and wherein its proximal end side is mounted to a tip portion of a robot arm, the tool replacing device comprising:
 a substantially cylindrical case member having a first extension portion and a second extension portion that extend toward an outer diameter direction of the tool replacing device, and that are located on the distal end side and the proximal end side, respectively; 
 a substantially cylindrical holding member located on a distal end side of the case member, the holding member including:
 a third extension portion of which a proximal end side extends toward an inner diameter side of the tool replacing device, and which is located between the first extension portion and the second extension portion of the case member; 
 a fourth extension portion of which a distal end side extends toward the inner diameter side; 
 a fifth extension portion extending toward the inner diameter side, between the third extension portion and the fourth extension portion; and 
 
 a movable member located inside the holding member, and having a sixth extension portion that extends toward an outer diameter side of the tool replacing device, between its distal end side and proximal end side, and that is located between the fourth extension portion and the fifth extension portion, 
 wherein the case member supports the holding member between the second extension portion and the third extension portion via a first elastic member so as to be movable in a cylindrical axis direction of the case member, and has a shock sensor that is located at an end face on the distal end side of the second extension portion and that detects a movement of the holding member by abutting against an end face on the proximal end side of the third extension portion of the holding member moving in the cylindrical axis direction; 
 wherein the holding member supports the movable member between the fifth extension portion and the sixth extension portion via a second elastic member so as to be movable in the cylindrical axis direction of the holding member, the holding member includes:
 a fluid supply hole for supplying a fluid to an end face on the distal end side of the sixth extension portion, and moving the movable member toward a direction opposite to a direction of a resilient urging force of the second elastic member, the fluid supply hole being located at an end face on the proximal end side of the fourth extension portion; 
 a seventh extension portion extending from an end face on the inner diameter side of the fifth extension portion toward the distal end side; and 
 a projection hole formed so that an engaging ball held between the movable member and the holding member is projectable toward an inner peripheral surface side of the holding member; and 
 
 wherein the movable member includes:
 an extruding surface that projects the engaging ball from the projection hole toward the inner peripheral surface side of the holding member by the end face on the distal end side of the sixth extension portion resiliently urged by the second elastic member abutting against the inner peripheral surface of the movable member, opposite to the engaging ball when the end face on the distal end side of the sixth extension portion abuts against the end face on the proximal end side of the fourth extension portion; and 
 a groove portion for accommodating the engaging ball that has moved from the projection hole to the inner peripheral side of the movable member when the sixth extension portion has been pressed against the resilient urging force of the second elastic member by the fluid supplied through the fluid supply hole and the movable member has moved to the proximal end side, the groove portion being located in the inner peripheral surface of the movable member, opposite to the engaging ball. 
 
 
     
     
       3. The tool replacing device according to  claim 1 ,
 wherein the first elastic member and the second elastic member are each a spring; and 
 wherein the springs are arranged along the circumferential direction of the case member at a determined spacing. 
 
     
     
       4. The tool replacing device according to  claim 2 ,
 wherein the first elastic member and the second elastic member are each a spring; and 
 wherein the springs are arranged along the circumferential direction of the case member at a determined spacing.